A　series　of　Co-Al　mixed　oxides　were　prepared　by　co-precipitation　method　via　Co-Al　layered　double　hydroxides　(LDHs)　as　precursors.　The　influence　of　chemical　compositions　of　Co-Al　LDHs　on　the　structural　and　physicochemical　properties　of　Co-Al　mixed　oxides　as　well　as　their　catalytic　performance　for　benzene　total　oxidation　was　investigated.　The　samples　were　characterized　by　using　ICP,　N2　physical　adsorption,　XRD,　TG-DTA,　SEM,　TEM,　Raman,　H2-TPR,　and　XPS　techniques.　The　characterization　results　showed　that　calcination　of　Co-Al　LDHs　gave　rise　to　Co(Co,　Al)2O4　spinel-like　mixed　oxide　as　the　main　phase.　The　crystallite　size　of　Co(Co,　Al)2O4　spinel　(6　∼　19　nm)　decreased　with　decreasing　the　Co/Al　molar　ratio,　suggesting　the　inhibition　of　crystal　growth　by　the　incorporation　of　Al3+　ions　in　the　spinel　phase.　A　drastic　change　in　the　state　of　Co-Al　mixed　oxide　occurred　at　Co/Al　=　6,　as　indicated　by　H2-TPR　and　XPS.　In　benzene　total　oxidation,　the　activity　of　Co-Al　mixed　oxide　increased　with　increasing　the　Co/Al　molar　ratio,　with　the　highest　activity　at　Co/Al　=　5;　further　increase　in　the　Co/Al　molar　ratio　to　6　led　to　significant　decrease　in　the　activity,　properly　caused　by　the　change　of　surface　state　of　mixed　oxide.　The　50　h　long-term　stability　test　revealed　that　the　optimized　Co-Al　mixed　oxide　was　stable　for　the　total　oxidation　of　benzene.　©　2015　Elsevier　B.V.　All　rights　reserved.